Panasonic RP-TCM125 Review (Budget IEM)

[maverickronin]

Thank you for clarifying. So this is a crystal IEM?

View attachment 126139

By the current enthusiast nomenclature, yes. It's a short and easy acronym so it stuck.

 

[marv]

Yes, folks, we are getting into measurements of IEMs!

I have been waiting for IEM reviews! thanks Amir for the effort

 

[respice finem]

Since iem phones eliminate the pinna what does that do to the head stage? Seems they might be better for binaural recordings.

This, and, the EQ applied will be almost universal IMHO (little dependence on user anatomy). IEMs sit in proximity to the eardrum and have a good seal (if the user is vigilant). The anatomical factor of outer ear size, shape and angle is out of the equation, with only the shape and diameter of the ear canal remaining. I'm looking forward to see more IEM tests, big kudos @Amir.

 

[amirm]

Thank you for clarifying. So this is a crystal IEM?

Man that brings back memories. First project ever was an AM radio with these crystal earphones! Used to use them in reverse as a microphone for RF transmitters I built.

 

[respice finem]

Absolutely.

Actual industry reference standard speakers referred to as studio monitors I have no problem with. But with every little powered 2 way fiasco-in-a-box having " studio monitor" printed on it these days, the term is bastardized beyond any meaning.

It started a long time ago, for sure. "Reference/Monitor" used to mean the absolute top model or range, not tacked on anything to make people buying cheap junk believe it was something special.

Plenty of JBL speakers were and are studio monitors. Several Yamaha speakers have been studio monitors. Several AKG headphones are/were industry monitor cans. As for IEMs, surely that is a professional designation for those things they wear on stage, not $14.99 Panasonic earphones for music on the go?

Amir's Salon 2s are not studio monitors and yet they are a TOTL speaker. They are a reference speaker.

Probably too late to "save" the term "monitor" anyway. Even "studio monitors" are all over the place nowadays, since some manufacturers have noticed there's a wider market for those.

 

[Robbo99999]

Nice, such value once EQ'd! I think I would have aligned the target on the measurement at the 1kHz point which would have aligned the treble better, allowing for easier EQ of the treble as it would be a closer fit prior to EQ.....then you'd use a Low Shelf cut filter at about 900Hz to remove a large amount of the overhanging bass and lower mids, and a couple of peak filters to further shape up that area.

 

[amirm]

BTW, forgot to mention that in the research, this headphone got a score of 25 whereas meeting the target got 67.

 

[respice finem]

Hence the headless panther without EQ?
The distortion figures and the performance after EQ show the potential of these little thingies. Maybe I can get used to my IEMs, so far they are mostly collecting dust TBH, somehow I can't forget having them in my ears...

 

[amirm]

Hence the headless panther without EQ?

Yes although that rating came from me listening to it and confirming the measurements.

 

[amirm]

o avoid sweaty earphones outdoors in south Florida, where I lived for over 30 years, I resorted to IEMs.

Even though we have much cooler temps here, as you I switch to IEMs during summer. What is comfortable otherwise, becomes sweaty when you wear big earmuffs!

 

[restorer-john]

Man that brings back memories. First project ever was an AM radio with these crystal earphones! Used to use them in reverse as a microphone for RF transmitters I built.

Same here! AM transmitters were awesome in the 1970s weren't they? I actually had to go looking for that ancient earphone. The electronic kit I got as a 8 or 9yo came with that earphone and I kept it all these years, as it has fond memories attached.

A few years ago I found a mint 150 in1 kit at a thrift store for a few dollars. The one all the kids lusted after. Bought it just because.

https://www.audiosciencereview.com/forum/index.php?threads/march-audio-hpa1.4430/page-19#post-440664

 

[ZolaIII]

Even though we have much cooler temps here, as you I switch to IEMs during summer. What is comfortable otherwise, becomes sweaty when you wear big earmuffs!

I switched to open earbuds on the go for both comfort and heat. IEM's aren't that cool when things get hot and it gots sweaty anyway thanks to their seal. Earbuds have their own downs (as every design) like bass roll off under 70 Hz similar to speakers and harder to fit in perfectly and don't provide good sound isolation obviously.

 

[Maiky76]

Hi,

Here are some thoughts about the EQ.

Notes about the EQ design:

• The average L/R is used to calculate the score.
• The resolution is 12 points per octave interpolated from the raw data (provided by @amirm)
• A Genetic Algorithm is used to optimize the EQ.
• The EQ Score is designed to MAXIMIZE the Score WHILE fitting the Harman target curve with a fixed complexity.
  This will avoid weird results if one only optimizes for the Score.
  It will probably flatten the Error regression doing so, the tonal balance should be more neutral.
• The EQs are starting point and may require tuning (certainly at LF).
• The range above 10kHz is usually not EQed unless smooth enough to do so.
• I am using PEQ (PK) as from my experience the definition is more consistent across different DSP/platform implementations than shelves.
• With some HP/amp combo the boosts and preamp gain need to be carefully considered to avoid issues
• Occluding IE devices generally must have very good fitting/seal in the user's ear canal for best performance.
  please spend a few minutes to pick up the best ear tip... Best optimization you can make otherwise the FR/Score/EQ presented here are just worthless.
• Just select the tip based on
  1. more bass = better seal
  2. More isolation from the outside world = better fit
  3. Comfort

Very good L/R match.

I have generated one EQ, the APO config files are attached.

Score no EQ: 9.6
Score Armirm: 74.2
Score with EQ: 108.5

Panasonic RP-TCM125-A APO EQ Score 96000Hz
April252021-143033

Preamp: -9.7 dB

Filter 1: ON PK Fc 161.7 Hz Gain -9.55 dB Q 0.33
Filter 2: ON PK Fc 889.5 Hz Gain 2.56 dB Q 0.92
Filter 3: ON PK Fc 4774 Hz Gain -5.25 dB Q 5.07
Filter 4: ON PK Fc 7063 Hz Gain 10 dB Q 2.51

 

[GWolfman]

Cool, thanks!

I'll wait and buy some that at least have a decent/good score without EQ should I need to use them in a pinch when EQ isn't available. Keeping my eyes open.

Amir, I'll have to send you my IEMs for measurements. Thanks again!

 

[paolomo]

Good luck with this new chapter, Amir! I must admit that I rediscovered IEM thanks to this forum. Now we have reviews too, that’s great. Regarding the bass heavy stock tuning of these Panasonic, it seems a rather ubiquitous thing. I’m EQing my Shure SE215 with a similar filter profile (nothing fancy in my case).

 

[charleski]

Thank you for clarifying. So this is a crystal IEM?

View attachment 126139

Crystal IEMs! Of course! There’s a huge gap in the market begging to be filled by an IEM using singing crystals that release your creative energy. Price it north of $3k and it would sell like hot cakes.

 

[respice finem]

Prior art https://en.wikipedia.org/wiki/Piezoelectric_speaker

 

[amirm]

Score no EQ: 9.6
Score Armirm: 74.2
Score with EQ: 108.5

Talk about breaking all records with EQ!!!

While I have you here, do you need both of the files I export? If it is just one, let me know so I can save the work to create the other.

 

[amirm]

Question for you IEM heavyweights: are the tips universal on these IEMs? I like to buy a bunch so I can use a fresh one for testing.

 

[Merkurio]

Great news!

IEMs are, by far, my favorite type of transducers due their comfort, low distortion and overall response (reaching very low registers with less messiness around the entire range).

Spacial qualities are the only thing IEMs not excel at, but even though, they’re models like the Audeze iSINE/LCDi line which brings almost headphone-like experience in a much more convenient form factor.